Regulator valve



Jan. 24, 1950 E. F. LOWEKE REGULATOR VALVE Filed Aug. 31, 1946 N UH w an T M9 QMT UK/NLK Patented Jan. 24, 1950 ErWin F. Lo wke, Jab

:zmesne r'zas'slgnments,

The B. iGoddrich sGompan'y, .1 Akron, Ohio, aecorporaitionmfiiNew lYork "'Ihe present'- invention izitestoimprovements in power bra'ke valyes for'ireducing="the pressure to the brakes from ithe mam pressure 'source, being a f-u'rther deve'lopment or the regulating valve=structure 'disclosed i-rr' mymopending application,'*-Ser ial"No. 545;fi38;"filed dulyii9, l944, now abandoned.

l One 6f the-obj ects-o'f the' invention is to 'provi'de an improved valve :of the typedesci ibed.

Another object is to provi'de an improved arrangement of the choke and displacement and regulating chamber over "that disclosed in my copendin'g applicationfor producing a delayed loa'd feeP' Ior noncompressible fiuids.

' "These and other objects arid advantages residing 1 in the -specific consltruction of "parts, and combination rand arr-angemeI-it *thereof will *be more:'fiilly appreciated from" a consideration 6f the tol'l'owing *speci'fication ana the -=-apperided claims.

-In'the drawings,

"-Fig. T I is a side e'elevation'al view 'of =a "power brake-valve partlyshow-n in-broken "vertical= sectiongand Fig. lI is an'eniargedTragmentaryvertical section of the construction -shown"inEig; "I.

'Ihe'power brake valve ifl has an inlet chamber I2 to conduct-a noncompressible fluid from some suitable pressure source,.csuchassanwaccumulator, to the inlet side of anunbalanced valve l4 controlling ;the-aflow. ofafluidpressurer eto ether/inlet! 6 through which the flow of fluid pressure to the utlet or brake chamber cl8 .is-c.ontrolled. The chamber i8 is 'hydraulica'l'ly connected with the brakes, 'with the return :fiiuid 1' from the i-brakes passing? through the ..openi1,1g-20 .6f the ,atubiilar valve Vpartr22, with the: flowsdfzreturnifiuidfto the return ior; exhaust chamberzz4izregulate'dtbyra valve part 25 engaging with the seat 28 of the valve part 22.

The valve I4 is of an unbalanced structure due to the fact that the diameter of the cylindrical portion 30 guided in the sleeve 32 is smaller than the diameter of the inlet I6, with the result that the pressure in the inlet chamber l2 functions to hold the valve l4 to its seat with the valve closed. The degree of unbalance is controlled through a compression spring 34, having one end reacting against the valve I4 and the opposite end against an adjustable abutment 36 supported in a threaded collar 38 with unitary movement between the parts 36 and 38 being provided through a pin connection 40. A screw driver slot 42 is provided as a convenient manner of adjusting the abutment 36 axially of the valve [0 :to reg-ulatethe "reaction of the "spring '34 againstthe valve14. As more clearlv-shown in Fig; II, the valve 'I='4-"is moved *from its seatby the pin portion 44 a'shown-as-' an integral" part (if the tubular valve partZ-Z.

The valvepart 26*is supported inthe" member 4E and guided "for 'aiiial movement in" the sleeve 48. As more ciearly shown =in-F ig. II, achoke passage 58 :is "provided in" the valve part 26 with a' wire '52"o'f correctlyselected-diameter located in "'the' passage "-50 "to reduce the "effective :v-area diameter of the -passage 5!) and provide'thedesired ohoke action. -At itsinner end 'the'passage tin-"communicates with a'passage '54 "providedzin the "member 46 'to-provide fluid "communication between the choke; passage 50 and the displacement' and regulating chamber 56,; having:an enlargement to receive the -axially movable load feel piston58.

The spring '60 acts against the rmember 46 holding the same contact'with the axially displaceable push ,rod 6 2,, which iSfDI'OVidd with a socket"-64=-at' its outer end andhaving alow rate spring -66 'housed therein and providing "an operating link through theassembly 68 withthe hi'ghrate laminated spring "10 "pivoted at T2 and actuatedbythe'rdd-"M operatively'connectedwith the-piston 16.

"The' fluid'iconnection with the'master cylinder actuated by the foot pedal in'parwell-"known "manner ismade -at 18"Withifluid"pressure' created by the-pressure 'onthefoot -pedal being "directed into the chamber I8 against the headof "the: piston.

Movement ofthepiston'lfi" to'the "right as shown in Fig. I; resultsin the rodsfitbeingmove'd to the left. Such--movement bringsxth'e valve part26 into' seating ;-engagement"'with the tubular valve part "22"with -continued "movement moving the valve l4 from its seat upon engagement by the pin 44. As the valve I4 is unbalanced, as soon as the valve I4 is cracked from its seat, energy stored up in the low rate spring 66 because of the unbalanced condition of the valve, is released to rapidly increase the area of the valve opening. An emergency operation of the brake valve In is provided through an air connection 80, with the air pressure being directed against the piston 82, which is shown in Fig. I abutted against the piston 16, and is capable of moving the piston 16 to open the valve M in a manner similar to movement of the piston 16 by fluid pressure from the master cylinder through the connection 18.

The delayed load characteristic of the power brake valve H1, in the illustrated form of the invention, is accomplished through the restricted flow of pressure through the choke 50 into the displacement and regulating chamber 56. This restricted flow of fluid pressure acts against the load feel piston 58 to displace the same to the right against the tension of the spring 84. The rate at which the piston 58 is moved to the right and the time interval between its initial movement and its engagement with the shoulder 86 of the push rod 62 determines the delay in the load feel through the springs 66 and back against the operators foot on the brake pedal. By selecting the proper size wire 50, this delay may be increased or decreased without any other structural change in the production of the valve In.

To briefly describe the operation of the power brake valve, in the terminology of the appended claims, the relatively noncompressible brake fluid flows from the source of fluid pressure, such as 4 an accumulator, into a pressure inlet chamber comprising chamber [2. With the valve I4 cracked from its seat, the fluid from the pressure inlet chamber flows past the valve l4 and with high initial acceleration assisted by the bafile or jet 88, flows into a pressure chamber, comprising the chamber l 8, from which it is conducted to the brake cylinders on the wheels. Following brake application, fluid pressure from the wheel brakes is returned through the port 20, flows axially through the valve part 22, between the valve part 26 and its seat 28, into a pressure return or exhaust chamber comprising the chamber 24, from which it flows into the fluid supply. Fluid pressure flowing through the choke 56 into the passage 54 flows into a dual purpose chamber, comprising the chamber 56, which is enlarged to receive piston 58. This dual purpose chamber functions first as a displacement chamber in that the piston 58 has initial movement relative to the rod 62 and after this initial movement it functions as a regulating chamber with the piston 58 engaging with the wall 86 and influencing the movement and position of the rod 62.

Having thus described my invention, what I claim as new and desire to cover by Letters Patent is:

1. A power brake valve comprising a main valve body, a plurality of coaxial chambers, including a pressure inlet chamber, a pressure outlet chamber, a pressure exhaust chamber, and a pressure regulating and displacement chamber, a first movable valve part located between said pressure inlet and pressure outlet chambers, a second movable valve part between said pressure outlet cham ber and said pressure exhaust chamber, said movable valve parts being in co-axial ali nment, a choke extending coaxially through said second movable valve part and placing said regulating and displacement chamber in restricted isolation from said pressure outlet chamber, movable means having an operative connection with said movable valve parts, displacement means in said regulating and displacement chamber actuated by the restricted flow of fluid pressure through said choke to delay the pressure build up in said regulating and displacement chamber, said dis placement means being constructed and arranged to have an initial movement to increase the volume of said regulating and displacement chamber independently of said movable means, and an operative connection between said movable means and said displacement means efiective following said initial movement. 7

2. A power brake pressure regulating valve for aircraft and the like for use in a brake system using a non-compressible operating liquid under pressure for brake actuation, said valve comprising a main hollow body part, a plurality of chambers defined in said body part and including a pressure inlet chamber, a pressure outlet chamber and a pressure regulating and displacement chamber, a movable valve part located between said inlet and pressure outlet chambers and adapted to control the flow of the pressure liquid therebetween, another movable valve part located between said pressure outlet chamber and said pressure regulating and displacement chamber, a choke extending through said last mentioned movable valve part placing said last mentioned chamber in restricted isolation from said pressure outlet chamber, common actuator means for said movable valve parts, the latter being moved one by the other in the operation of said actuator means to apply the brake, displacement means in said regulating and displacement chamber actuated by the restricted flow of liquid pressure through said choke to delay the pressure build-up in said regulating and displacement chamber, said displacement means being constructed and arranged to have an initial movement to increase the volume of said regulating and displacement chamber independently of said actuator means, and an operative connection between said actuator means and said displacement means effec- ,tive following said initial movement to produce a delayed load feel against said actuator means. ERWIN F. LOWEKE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,855,348 Hamilton Apr. 26, 1932 2,275,338 Andres et al Mar. 3, 1942 2,404,122 Campbell Jul 16, 1946 

